Each of such carbon disk brate rotors includes drive notches receiving drive keys connected to the wheels. The notches are trapezoidal in shape such that the thrust of the keys against the driving flanks of the notches is directed inwardly relative to the disk in order to withstand shear forces effectively.
It is conventional to fit metal reinforcing riders onto the portions of the disk between the notches in order to take up the reaction forces from the keys and distribute them over the disk rim between successive notches. These riders are fitted over the rim portions and they are riveted through the thickness thereof.
A first type of rider is constituted by a piece of metal folded into a U-shape with the bottom of the U being curved to completely cover the disk rim between two notches. The ends of this rider are machined so as to lie in the same planes as the drive faces delimiting the rim portion. However, on assembly, it is practically impossible to cause each of the ends to coincide with the plane of the corresponding face. The position of each rider on the disk is determined by its rivets passing through orifices in the sides of the U-shape and through the rim portion of the disk, said orifices being prepared in advance through the parts in locations which can only be determined with reference to these sloping ends or faces. Unfortunately, such determination is degraded by random error by virtue of the sloping nature of the reference faces and the resulting inaccuracies in measurement and in inspection.
This lack of coincidence leads to providing riders in such a manner as to ensure that their end edges always project beyond the flanks of the notches so that the keys bear on the end edges. It should also be underlined that this thrust is always accompanied by the key sliding relative to the disk in the plane of the drive surface, with the sliding being caused by: elastic deformations which cause the wheel to ovalize; deformation of the axle supporting the wheel; misalignment between the axes of the rotor and the stator; . . . . As a result, this first type of assembly gives rise to rapid wear of the end edges of the riders.
A second type of rider provides a solution to this problem which is satisfactory, in part. These riders are stamped metal pieces capping respective corners of the rim portions level with each notch face, with the caps thus covering the drive faces of the rotor disk. Each of these riders is also riveted to the disk and its positioning does not give rise to special difficulties. However this solution increases the number of parts used and therefore complicates manufacture.
The object of the invention is to provide a carbon disk brake rotor fitted with a plurality of one-piece reinforcing riders fitting over the peripheral portions between consecutive notches and additionally covering the drive faces of the notches while nevertheless being easy to put into place by conventional means.